MLAs voted to extend the National Crime Agency’s powers to Northern Ireland yesterday.

The motion was passed after the SDLP changed its position to back the move.

Dolores Kelly said increased accountability measures meant the UK-wide crime fighting unit could now operate with the “broad” support of the local community.

The Upper Bann MLA added: “It is in the public interest that the full resources available to the law enforcement agencies here in the North should be in place, in order for them to go after the criminals.”

The SDLP has been involved in seven months of negotiations with organisations including the Justice Department, the NCA and the PSNI.

The party was also in touch with the Home Office and on Monday night received a crucial letter from Theresa Villiers promising the NCA would not have a counter-terrorism role.

The NCA was set up in October 2013 to tackle serious and organised crime across the UK.

At present its remit in Northern Ireland includes customs, tax and immigration.

But, under legislation due to be passed at Westminster within three months, the covert agency would take on responsibilities for fighting cross-border crime, child exploitation, people trafficking, money laundering and internet abuse.

It will also have civil recovery powers and could be used to “follow the money” in cases like a massive illegal dump recently discovered near Derry.

The new agency will have to adhere to the same Code of Ethics as the PSNI and co-operate with the Police Ombudsman.

The Policing Board is tasked with overseeing the PSNI and will also have full scrutiny powers while the chief constable will have primacy over NCA operations.

The Home Secretary would not have veto powers. Sinn Fein has opposed the NCA’s full implementation over concern about accountability.

North Belfast MLA Gerry Kelly told the Assembly: “At the moment, MI5 has no arresting arm. The question is will the NCA then become that arresting arm?

“At the moment, when the PSNI takes over any operation, it is accountable under all the accountability mechanisms. That is the safeguard.”

Urging MLAs to support the motion, Justice Minister David Ford said Northern Ireland had been at a disadvantage for the past 16 months by crime gangs who perceive it as “easy picking”.

He added: “We can wait no longer. What we now have is an extremely high level of accountability.”